Process for the prepn. of cell-free penicillin-acylase by fermenting a strain of E. coli which produces this enzyme. The intracellular enzyme is separated form

摘要

Prepn. of cell-free penicillin-acylase by fermenting a strain of E. coli which produces this enzyme. The intracellular enzyme is separated from the culture liquid at controlled temps. between 0-50 deg.C by fast removal of the cell material through a slot or opening at a pressure of at least 500 psi but below the pressure which would badly tear the cells. The removed cell material is then stirred in water for 0.1-5 hrs. at 10-50 deg.C to dissolve the enzyme; this is extracted from the inactive cell material in aqs. soln. The cell-free enzymes are used for the prodn. of 6-APA and are esp. suitable for direct removal of side-chains of natural penicillins, esp. the side-chains of benzyl penicillin. The enzymes may be used as starting materials for chemical modification of the enzyme, giving products with higher activity and/or wider technical application.